Differential feed adjuster



Jan. 16, 1968 H. CIECIOR ETAL 3,363,593

DIFFERENTIAL FEED ADJUSTER 5 Sheets-Sheet 1 Filed Jan. 21, 1966 fol i uvvizmmas HEINRICH c/sc/oe 5066A! MA /ER ATTORNEYS.

Jan. 16 1968 H. CIECIOR ETAL 3,36

DIFFERENTIAL FEED ADJUSTER 3 Sheets-Sheet 2 Filed Jan. 21, 1966 INVENTORS HEINRICH CIECIOR EUGEN MA/ER ATTORNEYS.

Jan. 16, 1968 H. CIEClOR ETAL DIFFERENTIAL .FEED ADJUSTER ssheets-sheet 5 Filed Jan. 21, 1966 mvEwzgg l/E/N my c 506% MA/E'R ATTORNEYS.

United States Patent 3,363,593 DIFFERENTIAL FEED ADJUSTER Heinrich Ciecior, Ettlingen, Baden, and Eugen Maier,

Karlsruhe, Baden, Germany, assignors to Industrie-Werke Karlsruhe Aktiengesellschaft, Karlsruhe, Germany Filed Jan. 21, 1966, Ser. No. 522,063- Claims priority, application Germany, Feb. 4, 1965, J 27,449 Claims. (Cl. 112209) This invention relates to sewing machines of the type provided with supporting arms having a main work feeding means and a differential work feeding means feeding the work longitudinally of the arm relative to a throat plate. More particularly, the present invention is directed to a novel arrangement, in such sewing machines, for adjusting the inclination of the differential work feeding means relative to the throat plate and for adjusting the relative horizontal alignment of the differential feed ing means with respect to the main Work feeding means.

It is known, in the sewing machine art, that a wide range of inclinations of a differential work feeding means relative to the throat plate is one of the prerequisites for obtaining the best sewing results. In particular, special requirements must be met with respect to sewing synthetic materials. In sewing one type of synthetic material, an exact differential feed close to the needle is required whereas, in sewing another type of synthetic material, an exact differential feed remote from the needle is required. These requirements are based upon the necessities of the particular sewing technique used in sewing these materials.

Up until the present, attempts have been made to meet this requirement for a wide range of inclinations of the differential feeding means relative to the throat plate by placing washers or shims under the bearing surface of the differential feeding means, or by reworking this bearing surface by grinding or the like to attain the desired inclination. Adjustment of the inclination of the differential feeding means relative to the throat plate by the expedients tried hitherto is only a make-shift solution which, in addition, is very expensive because, once a respective differential work feeding means has had its inclination relative to the throat plate adjusted in the manner hitherto used, it can be used for sewing only one type of material. To sew another type of material, the thus adjusted differential feeding means must be replaced by another differential feeding means.

When sewing in a normal manner with a non-inclined setting of the differential feeding means, it is necessary that there be horizontal coincidence between the main work feeding means and the differential work feeding means. Due to manufacturing tolerances, this necessitates a later adjustment of the relative alignment of the two work feeding means. Such alignment has been affected, up to the present, in the disadvantageous manner mentioned above.

An object of the present invention is to provide a sewing machine with a supporting arm, and including a main work feeding means and a differential work feeding means feeding the work longitudinally of the arm toward the throat plate, and further including novel means for adjusting the inclination of the differential feeding means relative to the throat plate and relative to the main work feeding means, and which is free of the disadvantages of prior art adjustment expedients.

Another object of the invention is to provide, in a sewing machine having a supporting arm with main Work feeding means and differential work feeding means feeding the work longitudinally of the supporting arm toward the throat plate, novel means for adjusting the inclination of the differential work feeding means relative to the main work feeding means, and including means pivotally and slidably supporting the carriers for the two work feeding means intermediate their ends.

A further object of the invention is to provide an improved adjusting means for the differential work feeding means of the type just mentioned in which the carriers for the main work feeding means and the differential work feeding means are guided and supported in the supporting arm of the sewing machine directly adjacent each other or in sliding engagement with each other.

Still another object of the invention is to provide an improvement, of the type mentioned in the preceding paragraph, in which the two carriers are slidably supported on a slide which is oscillatable about a common bolt extending transversely of the supporting arm intermediate the ends of the carriers.

A further object of the invention is to provide an adjusting means for the differential work feeding means of a sewing machine having a supporting arm and in which the carrier for the differential feeding means includes a forked rear end in which is engaged a slide mounted on an eccentric forming part of eccentric means mounted in the carrier for the main work feeding means and which is angularly adjustable about an axis extending transversely of the supporting arm.

Still another object of the invention is to provide, in an adjusting arrangement of the type just mentioned, a slide in the forked end of the carrier for the differential work feeding means, this slide receiving a bolt having a hexagonal head and which is adjustable angularly in the carrier for the main work feeding means and has an eccentric portion engaged in the slide, whereby adjustment of the relative inclination of the differential work feeding means may be effected by applying an adjusting torque to the hexagonal head of the bolt.

Still a further object of the invention is to provide an adjusting means of the type mentioned in the preceding paragraph in which the adjustment may be maintained by a set screw engaged with the bolt and in which the bolt is fixed against axial displacement by a suitable screw clamp.

Another object of the invention is to provide, in a sewing machine of the type having a supporting arm in which are mounted a main work feeding means and a differential work feeding means feeding the work longitudinally of the arm toward a throat plate, means by which the inclination of the differential work feeding means relative to the throat plate, and the relative alignment of the main feeding means and the differential work feeding means, can be adjusted in a simple, rapid, and desired manner.

For an understanding of the principles of the invention, reference is made to the following description of a typical embodiment thereof as illustrated in the accompanying drawings.

In the drawings:

FIG. 1 is a longitudinal sectional view through the supporting arm of the sewing machine showing, in full, the carrier for the differential Work feeding means, and with the eccentric adjusted to its uppermost position;

FIG. 2 is a longitudinal sectional view of the supporting arm showing partly the carrier for the main feed ing means, and illustrating the eccentric in its lowermost position;

FIG. 3 is a transverse sectional view taken on the line 33 of FIG. 1; and

FIG. 4 is a perspective view, partly broken away, of the supporting arm but omitting its closing cover, throat plate and looper.

Referring to the drawings, a sewing machine is illustrated as having an inclined arm 1 to which a supporting arm 2 is secured by means of screws or the like 3. Within the supporting arm 2, there are arranged, in substantially parallel relation, a relatively elongated carrier 4 for a main work feeding means a relatively elongated carrier 5 for a differential work feeding means. Carriers 4 and 5 are arranged in side-by-side relation so that they can effect the necessary feeding movement. Intermediate their ends, carriers 4 and 5 are formed with substantially congruent rectangular apertures each receiving a rectangular block 7 or 6, respectively, for sliding engagement between the respective blocks and the carriers. The blocks 6 and 7 are pivoted on a common bolt 8 extending transversely of arm 2, as best seen in FIG. 3. Bolt 8 thus forms a fulcrum about which the inclination of a differential work feeding means 9 to a throat plate 10 may be adjusted, as well as the relative inclination between the main work feeding means and the differential work feeding means.

The rear end of carrier 5 is forked as at 5:1 to provide a substantially rectangular notch. Adjacent this notch, an eccentric bolt 11 is journalled, for angular adjustment, in carrier 4 for the main feeding means, this bolt 11 having a hexagonal head 11a engaging the remote side surface of carrier 5. As best seen in FIGS. 2 and 4, bolt 11 is maintained against axial displacement by means of a clamp 12 having a tightening screw 13. Hexagonal head 11a serves to adjust eccentric bolt 11 angularly, and a set screw 14 is threaded into carrier 4 to engage bolt 11 to maintain the desired setting. At its portion extending through fork 5a, bolt 11 has a circular eccentric portion 1115 which is journalled through a substantially rectangular slide 15 engaged in fork 5a.

After loosening set screw 14, eccentric bolt 11 can be adjusted by applying a wrench or the like to its head 5a thereby adjusting carrier 5, for the differential feeding means, angularly with respect to carrier 4, for the main feeding means, and also with respect to throat plate 10. Any relative angular inclination of feeding means 9 and 10 can be adjusted or pre-set, including a position in which the differential feeding means 9 and the main feeding means 16 are in substantially the same plane.

It will therefore be noted that the invention provides a simple and inexpensive means, forming a permanent part of the construction, and by which the relative angularity of the differential work feeding means relative to the main work feeding means, and relative to the throat plate, can be easily and readily adjusted.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. In a sewing machine including a supporting arm, a throat plate on the arm, a main work feeder adjacent the throat plate on one end of a first carrier, and a differential work feeder on a corresponding end of a second carrier; the improvement comprising means supporting said carriers in said supporting arm in substantiali 1y parallel relation for reciprocation along said supporting arm and providing relative angular displacement of said carriers; and eccentric means in said first carrier for angular adjustment about an axis extending transversely of said supporting arm and including an eccentric engaged in said second carrier; whereby, upon angular adjustment of said eccentric means, the inclination of said differential Work feeder relative to said throat is adjusted.

2. In a sewing machine, the improvement claimed in claim 1, in which said eccentric is engaged in the other end of said second carrier.

3. In a sewing machine, the improvement claimed in claim 2, in which said other end of said second carrier is forked; a slide slidable in said fork; said eccentric being engaged in said slide.

4. In a sewing machine, the improvement claimed in claim 1, in which said eccentric means comprises an eccentric bolt having a shaft angularly adjustable in said first carrier, and formed with said eccentric engaged in said second carrier; said bolt having a polygonal head engaging the remote side surface of said second carrier and providing for angular adjustment of said bolt.

5. In a sewing machine, the improvement claimed in claim 4, in which the other end of said second carrier is forked; a slide slidably mounted in said fork; the eccentric on said bolt being engaged in said slide.

6. In a sewing machine, the improvement claimed in claim 5, including means engaged with said bolt and restraining the same against displacement axially of itself.

7. In a sewing machine, the improvement claimed in claim 6, in which said restraining means comprises a clamp engaged with said bolt on the near side of said first carrier; and a screw for tightening said clamp.

8. In a sewing machine, the improvement claimed in claim 7, including a set screw threaded into said first carrier and engaged with said bolt to lock the angularly adjusted position thereof.

9. In a sewing machine, the improvement claimed in claim 1, in which said supporting means comprises a bolt extending transversely of said supporting arm intermediate the ends of said carriers; said carriers being formed with rectangular apertures therethrough substantially aligned with each other and said bolt extend ing through said apertures; and a pair of rectangular sildes, each engaged in the aperture of a respective carrier and each rotatable on said transversely extending bolt.

10. In a sewing machine, the improvement claimed in claim 8, in which said supporting means comprises a bolt extending transversely of said supporting arm intermediate the ends of said carriers; said carriers being formed with rectangular apertures therethrough substantially aligned with each other and said bolt extending through said apertures; and a pair of rectangular slides, each engaged in the aperture of a respective carrier and each rotatable on said transversely extending bolt.

No references cited.

RICHARD J. SCANLAN, JR., Primary Examiner. 

1. IN A SEWING MACHINE INCLUDING A SUPPORTING ARM, A THROAT PLATE ON THE ARM, A MAIN WORK FEEDER ADJACENT THE THROAT PLATE ON ONE END OF A FIRST CARRIER, AND A DIFFERENTIAL WORK FEEDER ON A CORRESPONDING END OF A SECOND CARRIER; THE IMPROVEMENT COMPRISING MEANS SUPPORTING SAID CARRIERS IN SAID SUPPORTING ARM IN SUBSTANTIALLY PARALLEL RELATION FOR RECIPROCATION ALONG SAID SUPPORTING ARM AND PROVIDING RELATIVE ANGULAR DISPLACEMENT OF SAID CARRIERS; AND ECCENTRIC MEANS IN SAID FIRST CARRIER FOR ANGULAR ADJUSTMENT ABOUT AN AXIS EXTENDING TRANSVERSELY OF SAID SUPPORTING ARM AND INCLUDING AN ECCENTRIC ENGAGED IN SAID SECOND CARRIER; WHEREBY, UPON ANGULAR ADJUSTMENT OF SAID ECCENTRIC MEANS, THE INCLINATION OF SAID DIFFERENTIAL WORK FEEDER RELATIVE TO SAID THROAT IS ADJUSTED. 